Datasheet LTC3646, LTC3646-1 (Analog Devices) - 3

LTC3646/LTC3646-1
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2), PVIN = SVIN = 12V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Input Supply (PVIN, SVIN)
VIN Input Voltage Operating Range l 4.0 40 V VIN(OV) Input Supply Overvoltage Lockout VIN Rising l 43.5 46 V Hysteresis (VIN Falling) l 2.0 2.5 2.9 V VIN(UV) Input Supply Undervoltage Lockout VIN Falling 3.2 3.35 3.5 V Hysteresis (VIN Rising) 250 mV IQ DC Supply Current (Note 3) Forced Continuous 620 875 µA Sleep Mode 140 190 µA Shutdown Mode VRUN = 0V 8 µA
Main Control Loop
VOUT Output Voltage Range (Note 4) LTC3646 2.0 30 V LTC3646-1 0.6 15 V VFB Feedback Reference Voltage –40°C < TA < 85°C 0.594 0.6 0.606 V l 0.591 0.6 0.609 V Feedback Voltage Line Regulation VIN = 4.0V to 40V, ITH = 1.5V 0.05 %/V Feedback Voltage Load Regulation ITH = 1.0V to 1.8V 0.12 % Feedback Input Current VFB = 0.6V l 0 ±20 nA gm(EA) Error Amplifier Transconductance External Comp 300 µS tON(MIN) Minimum On-Time VIN = 40V, RRT = 30k, VON = 2V 30 ns tOFF(MIN) Minimum Off-Time 80 ns ILIM Valley Switch Current Limit l 0.9 1.2 1.5 A Negative Valley Switch Current Limit –0.3 A Internal Oscillator Frequency VRT = VINTVCC 1.6 2.25 2.95 MHz RRT = 450kΩ 0.19 0.2 0.27 MHz RRT = 60kΩ 1.25 1.5 1.75 MHz RRT = 30kΩ 2.55 3.0 3.45 MHz External Clock Frequency Range 0.2 3.0 MHz RDS(ON) Top Switch On-Resistance (Note 5) VIN = 5.5V 200 mΩ Bottom Switch On-Resistance (Note 5) VIN = 5.5V 120 mΩ Switch Leakage VIN = VSW = 40V, VRUN = 0V ±1 µA VIN = 40V, VSW = 0V, VRUN = 0V ±1 µA
Internal VCC Regulator
VINTVCC INTVCC Voltage IINTVCC = 5mA l 4.8 5.0 5.2 V INTVCC Load Regulation (Note 6) IINTVCC = 0mA to 5mA 0.5 % INTVCC Undervoltage Lockout INTVCC Falling 3.0 V INTVCC UVLO Hysteresis 0.3 V EXTVCC Switchover Voltage EXTVCC Rising 4.25 4.5 4.65 V EXTVCC Hysteresis 200 mV
Operation
VRUN RUN Pin Threshold RUN Rising 1.17 1.21 1.26 V RUN Falling 1.06 1.10 1.14 V Hysteresis 110 mV RUN Pin Leakage Current RUN = 1.3V 0 ±1 µA VPGOOD(UT) PGOOD Overvoltage Threshold FB Rising 5.0 7.5 10 %VFB FB Falling 3.5 5 %VFB VPGOOD(LT) PGOOD Undervoltage Threshold FB Falling –5.0 –7.5 –10 %VFB FB Rising –3.5 –5 %VFB 36461fc For more information www.linear.com/LTC3646 3 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Operation Applications Information Typical Applications Typical Application Related Parts